Profile
The working group X-ray Radiometry is responsible for radiometry in the X-ray range and for the application of X-rays in dimensional nanometrology. Some of the activities are X-ray detector calibration, characterization of X-ray optical components, thickness determination of nanolayers and size and concentration determination of nanoparticles. The working group operates 3 beamlines at BESSY II in the spectral range from 1.6 keV to 10 keV and uses 2 additional beamlines in adjacent spectral ranges.
Research/Development
- Development of instrumentation for the characterization of silicon pore optics for the envisaged X-ray space mission ATHENA in cooperation with ESA
- Characterization of photoemissive detectors and multilayer mirrors for plasma diagnostics in cooperation with CEA (France)
- Characterization of large area hybrid pixel X-ray detectors in cooperation with Dectris Ltd. (Switzerland)
- Traceable concentration determination for nanoparticles with Small-Angle X-ray Scattering (SAXS)
- Characterization of nanoobjects with SAXS e. g. in cooperation with the Helmholtz-Zentrum Berlin (HZB)
- Characterization of nanostructured surfaces with GISAXS (Grazing Incidence SAXS)
Services
The following calibrations according to the 
quality management handbook of PTB division 7 are performed in the working group 7.21:
- Determination of the spectral responsivity of radiation detectors in the photon energy range from 1.75 keV to 60 keV (7.2-1.6, 7.2-1.9)
- Determination of the spectral reflectivity or spectral transmittance of mirrors and filters in the photon energy range from 1.75 keV to 10 keV (7.2-1.8)
- Determination of the thickness of thin layers on reflecting surfaces in the range from 2 nm to 1000 nm (depending on material) with X-ray reflectometry (7.2-1.11)
- Determination of the mean diameter of nanoparticles in suspension in the range from 3 nm to 300 nm with small angle X-ray scattering (SAXS) (7.2-1.12)
- Determination of the number concentration of spherical particles in suspension using small-angle X-ray scattering (7.2-1.15)
Information
- Calibration of X-ray detectors / cryogenic radiometry
- Characterization of optical components / reflectometry
- X-ray reflectometry for layer thickness determination
- X-ray radiometry for the characterization of astrophysical instrumentation
- Small-angle X-ray scattering (SAXS) for size determination of nanoparticles
- Grazing incidence SAXS (GISAXS) for the characterization of nanostructured surfaces